Provide `fancy-battery-mode', which is like `display-battery-mode' but with fancier display, and more customization options. Customize `fancy-battery-mode-line' to change the appearance of the battery status information. Take a look at `fancy-battery-default-mode-line' for the default value and for inspiration. Customize `mode-line-format' and `mode-line-misc-info' to change the position at which the battery status appears in the mode line. Typically it's at the very end after the minor mode list, so you may want to move `mode-line-misc-info` more to the front of `mode-line-format`.